Automatic switch lamp socket



Aug 1, 1939 J. w. HOBBS 2,167,756

AUTOMATIC SWITCH LAMP SOCKET Filed NOV. 18, 1938 Patented Aug. l, 1939 UNITED STATES PATENT, ori-"ICE W. Hobbs Corporation poration ol' Delaware Springileld, Ill., a cor- Application November 18, 1938, Serial No. 241,174

3 Claims.

'Ihe present invention relates in general to automatic switch lamp sockets and is more par. ticularly concerned with improvements in the construction of certain parts of socket devices of such character, whereby assembly during manufacture may be facilitated, which will result in more eflicient operation of the devices and longer life in service, and in which the parts which are subjected to the most wear may be easily and readily replaced.

It is a further object of the present invention to provide improved means in a socket construction of the herein-described character for connecting the contact parts thereof with a conduc- 15 tor connection.

A still further object is to provide in a socket construction wherein the socket contact parts and connected conductor are arranged to move as a Y unit when a lamp is put into or removed from .the socket, improved means for slidingly and insulatingly supporting the conductor for movement in an axial direction and conning any raveling of its insulation covering to the portion of the conductor disposed within the socket shell.

More specically, the present invention constitutes improvements in the construction disclosed in my Patent No. 2,107,570, issued February 8, 1938.

The above, further and other objects of the present invention will be apparent from the following description and accompanying drawing:

The accompanying drawing illustrates an embodiment of the present invention, and the views thereof are as follows:

Figure 1 is a longitudinal sectional view through a lamp socket embodying the features of the present invention, and showing the cooperative relationship of the parts when a lamp is inserted in v the socket and the socket is disposed in such a position that the circuit controlling parts thereof will be in circuit closed position.

Figure 2 is an enlarged plan view of the insulating support for slidingly suporting the hot conductor connection to the socket.

Figure 3 is a diametric sectional view through the supporting member, taken substantially on line III- III of Figure 2.

The drawing will now be explained:

As illustrated in Figure 1 of the drawing, my improved device comprises a metallic tubular shell I0 having one end contracted to form a lampreceiving socket portion II and deiines an inwardly spaced abutment shoulder I2 extending circumferentially of the shell. Abutting the shoulder I2 at its periphery is a washer I3 of suitable insulating material which forms a bottom for the socket portion II. The central opening of this washer vis adapted to receive therethrough the central contact connection I3 of a lamp I4 when it is inserted in the socket 5 portion of the device.

The opposite end of the shell I is provided with a metallic cap I5 having a press llt engagement with this end of the shell and provided with a central opening I6 at its closed end. 10'

`The interior of this end of the shell and the inner surface of the capped end portion is insulated by a member I'I having a relatively thin circumferentially extending flange portion I8 at one end, this flange portion being of such a diameter as to extend to the inner wall of the shell Ill. At its center, the member II is provided with an elongate sleeve portion I9 which extends through and outwardly beyond the opening I6 of the cap. The sleeve portion I9 defines an axially extending bore through the member.

Cooperating with the Washer member I3 and the insulating member I1 for insulating the interior of the enlarged portion of the shell I0, there is provided a tubular member 2I which is disposed with its ends respectively abutting the peripheral margin of the washer I3 and the ilange I8 of member I'l.

The above mentioned insulating members form an insulated compartment 22 within which there 30 is housed a cup-shaped container 23 having its bottom disposed towards the socket portion of the shell I0, this cup-shaped member being slidably movable Within the tubular insulating member 2 I.

Extending over the open end of the container J 23 is a disk 24 of suitable insulating material, this disk having its peripheral edge in sliding -engagement with the interior wall of the tubular insulating member 2| and mounting at its center a metallic contact member 25.

It will be noted that the contact member 25 extends to both sides of the disk 24 and that on the side thereof facing the chamber, is provided lwith a truncate-conical head portion 26 which is disposed within the cup-shaped member 23.

The end of contact member 25 adjacent the opposite face of disk 24 is beaded over to retain the contact member against removal from the disk.

Adjacently disposed to the disk 24 is a second f insulating disk 21 which is likewise positioned with its peripheral edge in sliding engagement with the interior Wall of the tubular insulating member 2I. This disk also supports a contact member at its center, one end of the contact u member being provided with a head portion 28 adapted to make engagement with the adjacent end-of contact member 25. The other end of the contact member extends axially from the disk 21 to provide a stern portion 29 having a central socket for receiving one end of a conductor 3l, which may be soldered or otherwise secured against removal in the socket 30.

'I'his conductor is preferably covered with an insulating covering such as woven fabric 32, and it will be noted that the conductor with its insulating covering is carried axially into the inlterior of the shell I0 through the sleeve portion I9 of the member I1, and that the inner end of the insulating covering is terminated at the associated end of the stem portion 29.

Surrounding the stem portion 29 and connected end of conductor 3| is a coil spring 33 having one end bearing against the ilanged portion of member I1 and its other end bearing against the insulating disk 21.

It will be noted that the coiled spring 33 acts to normally bias the movement of the cup-shaped member 23, the insulating disk 24, the insulating disk 21, and the connected conductor for movement as a unit towards the socket portion II of the device. Moreover, when a lamp I4 is inserted in the socket portion II, the central connection I3 engages against the bottom of the cup-shaped member and shifts all the parts against the pressure of spring 33, thus retaining pressure engagement between the current carrying parts including the engagement of the head portion 28 of the contact connected to the conductor with the contact 25. It will thus be seen that the connection and disconnection of a lamp to the socket will cause sliding movement of the conductor 3| and its insulation where it passes through the sleeve portion I9 of the support I1. It has been found that by making this sleeve portion of relatively long length wearing of the insulation is materially reduced and any raveling which takes place at the severed end thereof will be conned within the interior of the shell I0 and will not continue past the inner face of the member I1.

This arrangement results in advantages which are not obtainable where the usual insulating washer is utilized at this point. It has been found that when the ordinary type of washer is used,

4the comparatively thin inner edge of the washer soon wears through the insulation and permits exposed parts of the conductor to more readily come in contact with the metallic parts of the device, thus causingshort circuits and other troubles. y

The use of a separate terminal contact connected to the end of the conductor has been found to possess meritorious advantages over the previous practice of connecting the conductor directly to the contact which is disposed within the cup-shaped member. As shown, the cup-shaped member contains a plurality of gravitationally responsive conductor elements 34, such as conducting spheres, which are adapted under tilting movement of the device to assume positions out of contact with the head 26 or in contact withhead 26, for disconnecting and connectingthe hot conductor with the cup-shaped member 23.

It will be apparent that the head 26 will be subject to wear and that if this head is permanently connected as by soldering or the like to the conductor, it will be harder and more inconvenient to replace the contact unit 25 than in a case where the contact 25`is separately formed from the contact terminal connected to the conductor.

From the foregoing'- description, it will be apparent that the present invention provides an improved automatic switch' lamp socket in which the assembly of its parts during manufacture is facilitated; which includes a novel arrangement of parts resulting in eicient operation of the device and longer life in service; in which the parts that are subjected to the most wear may be readily and easily replaced; which includes improved means for connecting the contact parts thereof with a conductor connection; and which incorporates improved means for slidingly and insulatingly supporting the conductor connection for axial movements and confining any raveling of its insulation to the interior of the shell socket.

The invention has been described herein more or less precisely as to details, yet it is to be understood that the invention is not to be limited thereby, as changes may be made in the arrangement and proportion of parts, and equivalents may be substituted without departing from the scope and spirit of the invention.

I claim as my invention:

1. In a device of the character described, a tubular metallic shell adapted at one end to form a lamp receiving socket for engaging a circuit contact connection of the lamp, a metallic contact member insulatingly supported within said shell, said member defining a chamber, a contact member insulatingly supported at the open end of said chamber,` a hot conductor extending into said shell, one of said contact members being arranged to make electrical contact with another circuit contact connection of said lamp, and the other of said contact members having an electrical connection with the hot conductor.' spring means for resiliently opposing movement of said contact members and the hot conductor away from the socket end of the shell, a guide member of insulating material at the other end of said shell for lslidingly supporting the hot conductor for axial movements-said guide member being supported interiorly of said 'sh-ell, and freely movable gravity responsive conductor means movable within said chamber to connect and disconnect said contact members upon tilting movements of said shell.

2. In an automatic gravity operated switch lamp socket, a tubular metallic shell adapted at one end to form a lamp receiving socket, a cupshaped metallic member insulatingly supported for sliding movement within saidV shell, the closed end of said member being disposed towards the socket end of the shell for engagement by a circuit contact on said lamp, insulatigly supported contact means at the open end of s id cup-shaped member, a lrot conductor extending longitudinally into said shell and having connection with said contact means, spring means biasing said cupshaped member, contact means and hot conductor as a unit i'n a direction towards the socket end of said shell, an annular insulating member anchored at its periphery with respect to said shell, said insulating member having an elongate hub portion defining a bore for slidingly receiving and supporting the hot conductor therein, and freely movable gravity responsive conductor means.

movable within said cup-shaped member to connect and disconnect said cup-shaped member and contact means upon tilting movements of said shell.

3. In a device of the character described, a tubular metallic shell adapted at one end to form a lamp receiving socket, a closed metallic confor sliding movement in said shell, a spring acting to press the second contact into engagement with the iirst contact member, and freely movable gravity responsive conductor means movable within said chamber to connect and disconnect saidchamber and the rst contact upon tiltingY movements of said shell.

-\ JOHN W. HOBBS. 

